The usual approach to making eggnog is simple: Mix together eggs, sugar, and cream and fortify the dairy with your choice of booze. Then, bottoms up. But if you plan ahead, there’s a simple way to improve on this classic winter holiday cocktail: Simply let a batch of nog age for at least three weeks in the refrigerator before indulging. The rest period drives off the eggy taste while giving the other flavors a chance to meld. At the same time, the alcohol has a chance to kill any potential pathogens from the raw eggs.